Method and apparatus for producing glass fibers



March 9, 1943. s. M. DOCKERTY 2,313,630

METHOD AND APPARATUS FOR PRODUCING GLASS FIBERS Filed Sept. l2, 1959 2 Sheets-Sheet l H... o l' l lNvENToR Moclfert B/a/ ATTORNEY March 9, S M DQCKERTY METHOD AND APPARATUS FOR PRODUGING GLASS FIBERS Filed Sept. l2, 1959 2 Sheets-Sheet 2 INVENTOR MBocA/erqy, BY M/ wd;

ATTORN EY Patented Mar.Y 9, 1943 METHOD AND APPARATUS Foa PnonUcxNG GLASS FIBERS Stuart M. Dockerty, Newark, Ohio, assignor to Owens-Corning Fiberglas Corporation, a corporation of Delaware Application September 12, 1939, Serial No. 294,487

21 Claims. (Cl. 49-1) The present invention relates in part to a novel method and apparatus for producing brous material which may be either straight or undulated, and in part relates to novel types of crimped ber and tangled or felted mats of crimped fibrous material. The invention is primarily designed for use in connection with the production of fibrous glass material but the same may also be found useful in connection with fibrous material composed of other thermoplastic materials which are extruded or owed through an orifice.

The principal object of the invention is to provide a novel method of attenuating a glass stream issuing from an orifice associated with a glass feeder.

Another object of the invention is to provide such a method for producing glass fibers, together with an apparatus for carrying out the method, whereby in the event of interruption of stream ow, automatic resumption of attenuation will occur-upon restoration of the stream ilow, and thus obviate momentary shut-down during hand yfeeding of the ber to the attenuating means.

Yet another object ofthe invention is to provide a method for producing brous glass in which any shot or other unberized particles issuing with the stream may be automatically segregated from the finished product.

A still further object of the invention is to provide an apparatus for producing brous glass by an attenuation'process in which accumulated gobs or beads of glass, stone, or other foreign particles will pass through the apparatus unimpeded and will cause neither damage to the apparatus nor clogging thereof.

Another object of the invention is to provide such an apparatus which may be operated at high speeds and which has no moving parts that require synchronization with each other.

Another object. of the invention is to provide such an apparatus which is relatively simple in its construction in that it has but a single moving part and therefore is unlikely to get out of order or otherwise require attention.

Another object of the invention is to provide an apparatus of this character which maybe utilized in the production of either straight or undulated crimped brous glass at will by mere adjustment of the mechanical parts thereof, and/or the temperature of the molten glass, Without resorting to substitution, addition or elimination of parts.

The objects oi the invention thus far set forth are applicable to the production of either straight or undulated fibrous glass. Where undulated or wavy crimped glass is concerned it has heretofore been diflicult to achieve entanglement or felting of the crimped -bers'for the reason that the nature of the crimping has been such that the undulations of the individual strands or fibers were not of a character that they could penetrate the undulations of adjacent strands or fibers and remain locked thereto permanently. Undulations heretofore produced generally were of the character of a sine curve and could generally be pulled from one another so that the product had neither cohesion nor mass integrity in any direction.

It is another important object of the invention therefore, where undulated fibrous glass is concerned, to provide a method of and apparatus for crimping glass fibers in such a manner that during the crimping process actual loops, as distinguished from mere undulations, are formed that close about one another and retain their form permanently so that the loops cannot readily be separated. This results in a product inwhich the fibers are definitely interlocked with one another and an exceptionally good degree of cohesion is attained.

Another object of the invention is to provide an apparatus by means of which the final crimp applied to the fibers occurs automatically in the suspended fibers themselves without the aid of any mechanical means and without any parts, moving or otherwise, touching the bers during the formative stage.

Other objects of the invention not at this time enumerated will become apparent as the nature of the same is better understood.

In the accompanying drawings:

Fig. 1 is a sectional view, partially diagrammatic in its representation, of an apparatus for attenuating glass streams into fibrous glass;

Fig. 2 is a vertical sectional view taken transversely of Fig. 1;

Fig. 3 is a sectional view similar to Fig. 1 showing -a modified form of apparatus;

Fig. 4 is a sectional view taken transversely through a crimping drum employed in connection with another modified form of the invention;

Fig. 5 is a sectional view similar to Fig. 4 showing another form of crimping drum;

Fig. 6 is a diagrammatic view of a forming apparatus by means of which the crimped glass fibers are formed into a mat;

Fig. '7 is a sectional view similar toFig. 1

showing a modified form of crimping apparatus;

Fig. 8 is a vertical sectional view taken transversely and centrally oi' Fig. 7; 1

Fig. 9 is a sectional view similar to Fig. 1

showing an endless attenuating or crimping.

to attenuate the same. It is also contemplated,

if desired, to crimp the streams into wavy fibrous form of sinuous configuration. If the glass is suiilciently hot it may be projected, while still hot from the forming operation, into a quiescent atmosphere whereupon the preformed undulations in the fibers are transformed into partially closed loops which are capable of encircling one another to produce a mass of glass wool in which a relatively high percentage of interlocking between loops is effected.

Referring now to Figs. 1 and 2, the reference character I designates a glass feeding apparatus which may be of the type shown in the United States Patent No. 2,165,318. The feeder lll includes a series of orifices II from which streams I2 of glass issue continuously. The temperature of the streams I2 as they emerge from the feeder may, if desired, be regulated by means of blowers I3 positioned beneath the orifices II in a manner similar to that disclosed in the Slayter and Thomas Patent No. 2,234,986. The blowers I3 may or may not be used according to the type of stream desired.

Spaced below the feeder I0 and positioned substantially tangential to the streams I2 issuing from the former is an irregular cylindrical surface or crimping drum I4 which is preferably of squirrel cage" design and consists of a series of parallel crimping bars I5 arranged in cylindrical fashion and having their ends anchored in end plates I6 mounted on a central shaft Il. A spool-shaped spacing member I8 surrounds the shaft I1 and has its ends secured to the end plates I6. Any suitable means may be utilized for rotating the crimping drum I4, and as shown in Fig. l, an electric motor M is adaptable for this purpose,

'I'he streams or iibers I2 of glass issuing from the orifices II are directed tangentially against the crimping drum I4 by means of continuous lateral blasts of air issuing from a blower I9 through one or a plurality of superimposed series of jets 20 spaced apart a distance which will cause the blasts issuing therefrom to be directed simultaneously toward two or more adjacent interstices to crimp the streams or fibers l2 therein or at least to cause the streams to bear against the drum in such a manner that the frictional engagement between the drum and bers will be sufilcient to cause a definite gripping of the fibers to attenuate the streams issuing from the orifices II.

The blowers I3 may be regulated to cool the fibers l2 to such an extent that little or no crimping will take place on the crimping bars I5 or, if crimping is desired, these blowers may be regulated to permit the fibers t2 to arrive at the crimping drum in a relatively hot state. In the latter instance, because the crimping drum I4 is rotating at relatively high speed, the relatively hot fibers I2 are crimped and thrown out tangentially of the drum by centrifugal force 'as indicated at 2l. Inasmuch as the blasts are directed simultaneously into 'adjacent interstices in the drum I4, successive crimps formed by a single jetdo not neutralize eachother by taking up the slack of one another.v

The crimped fibers shown at 2I are generally of sinuous wavy conguration inasmuch as this is the form imparted to them while they are operated upon by the blasts of air which force them against. the moving crimping bars I5. If

` however the fibers as they leave the bars I5 have sufiiciently low viscosity due to heat, a further crimping action may take place. Because of the high rate of surface speed of the drum Il, the fibers as they are thrown tangentially therefrom move longitudinally of themselves at terric speeds in the neighborhood of from 4,000 to 50,000 feet per minute although other speeds may be employed. At these high speeds when the fibers have moved out of the range of air disturbance caused by rotation of the drum and/,or the air disturbance caused by the blasts issuing from the blower I9 and have moved into a region of comparatively quiescent air, they bump or telescope, so to speak, into the quiescent air,- are decelerated and pile up on each other to a certain extent so that loops 22 are formed. As the bers are collected haphazardly in the form of bulk brous glass, some of these loops close about o ne another to a certain extent to form a partially felted body of wool that has tenacity or coherence in all directions.

The crimped bers 2| may be passed through an opening 23 provided in a table 24 upon which for convenience the motor M may be mounted.

The crimped fibrous glass may be collected as it is formed upon a continuously moving surface or conveyor 25 (Fig. 6). Interfelting of the crimped fibers may be further enhanced by means of rollers 26 which operate upon the fibrous material to cause these so-called closed loops to penetrate one another and hook onto one another to produce a matted product that possesses exceptional tenacity in all directions and which, in order to be separated, must actually be pulled or torn apart. The rolls 26 may be driven in such a manner as to facilitate passage of the matted product therebeneath and also, if desired, they may be reciprocated longitudinally in order that the material may be thoroughly worked to produce a maximum amount of interfelting. A number of felting procedures are shown in the Slayter Patent No. 2,206,059, dated July 2, 1940.

It is to be noted that in the attenuation process wherein the streams or fibers I2 are actually drawn from the bottoms of the orifices I I, any stones, lumps or other untlberized particles issuing from the orifices will be discharged by centrifugal force shortly after they have contacted the drum while the bers I2 are carried further around the circumference of the drum than are the unberized particles. In order to collect these latter unflberized particles and conduct them from the apparatus, a chute 21 extends beneath the drum as shown in Fig. 1.

In Fig. 3 a modified form of apparatus for merely attenuating the fibers II2 without substantially crimping the same is shown. In this form of the invention the attenuating drum III is shown as being driven by means of a turbine T. A blower IIS utilizing a single slot or series of jets |20 which is made adjustable as to size by aaiaeao means of an adjustable plate |21 directs blasts of air substantially tangentially against the drum ||4 to maintain the fibers in frictional contact with the drum in order that attenuation thereof may be effected. Ordinarily only a small pressure of about one-half to two or three pounds per square inch of air is required to maintain the streams or fibers I|2 in engagement with the drum II4.

Inasmuch as the blast or blasts of air issuing from the jet or jets are directed more or less tangentially of the drum II4, the fibers in leaving the drum continue to move in the path of air disturbance as created by the jets |20 and consequently they are not flung suddenly into any region of quiescent air and therefore they are not telescoped in the manner previously described in connection with the apparatus of Fig. 1. The net result of this is to produce iibers which are either very slightly crimped or which are substantially straight.

By inclining the blower IIS so that the jet or jets |20 approach a radial direction, crimps of a progressively deeper nature may be effected in the fibers. In this form of the invention, the fibers on leaving the drum are projected into more quiescent air.

In Figs. '7 and 8 a suction box within the drum has been employed for the purpose of creating a partial vacuum on the inside of the drum in the tangential region where the fibers engage the latter. The blowers of the previously described form of the invention may be omitted, if desired, and the rarified atmosphere within the drum in this r'egion is relied upon to draw the fibers against or between the interstices of the crimping bars and perform the attenuating and, if desired, the crimping operation.

Accordingly, the drum 2I4 is mounted upon a hollow stationary shaft 2I'I which is formed with a series of apertures 24| within the drum that communicate with the interior of a suction box 242 mounted thereon by means of supporting spider arms 243. A driving motor M is provided with a drive shaft 244 into which one end of the shaft 2I'I extends and which is keyed as at 245 to one of the end plates 2I6 of the drum. The other end of the shaft 2I'| is connected by means of a suitable flexible conduit 246 with a source of vacuum.

The outer or forward end of the suction box 242 is curved to accommodate the curvature of the drum and is open and fits closely against the drum in the tangential region where the drum is contacted by the stream 2| 2 issuing from the orices 2| I. Suction within the box 242 is relied upon solely for drawing the straight streams or fibers 2 I2 into the interstices between the crimping bars 2 I5 to force the same against the drum and effect attentuation thereof and, if desired, to crimp the same. The crimping operation may be augmented by the use of a blower similar to that illustrated at I9 in Fig. 1 or at H9 in Fig. 3.

In Figs. 4 and 5 crimping drums 3I4 and 4I4 having modified forms of crimping bars or ribs 3I5 and 4I5 respectively are shown. In the former instance the crimping bars 3I5 are in the form of flat ribs arranged uniformly at slight angles to each other and spaced about the periphery of the drum and slanting outwardly in the direction of rotation of the drum in such a manner that the streams or fibers which are blown, drawn or otherwise forced into the interstices between the crimping ribs may readily emerge therefrom. This form of drum is useful in connection with a blower of the type shown in Fig. 1 at I9 inasmuch as the blasts of air directed radially into the drum will give an impetus' to the slanting vanes tending to rotate the same. In Fig. 5 the fiat crimping ribs 4I5 are radially disposed about the periphery of the drum, thus rendering a blower of the type shown in Fig. 3 at IIS adaptable for use with this type of crimping drum. It is obvious that either type 'of blower may be employed with either type of drum or, if desired, the suction box of Figs. 7 and 8 may be incorporated with these drums.

A somewhat more convenient method than that shown in Figs. '7 and 8 of partially vacuumizing the interior of the drum 5I4 is shown in Fig. 9 wherein a suction box 542 has an open forward end 541 shaped to' partially encircle the drum 5I4, leaving a tangential region 540 against which the fibers 5I2 may be forced by the action of one or more blasts of air issuing from a blower 5I9. The blower 5I9 may howeverfbe omitted and suction within the drum 5|4 relied upon solely for drawing the fibers against the drum.

In Fig. 10 there is shown an endless attenuating or crimping impeller 6I4 which may be employed in lieu of any of the various attenuating or crimping drums previously described. The impeller 6I4 includes a pair of sprocket chains one of which is shown at SI5 and which are mounted upon sprocket wheels 6I 6 and across which there extend a plurality of spaced crimping bars SI1 designed to operate upon the fibers 6I2 in the manner previously described in connection with any of the other forms of the invention. A blower 6I9 may be employed for directing blasts of air against the streams SI2 to force the same against the crimping bars 6 I 5, or if desired, a suction box 642 that operates in the manner of the suction box 242 of Figs. '7 and 8 may be employed to draw the'iibers into engagement with the crimping bars SI5. Under certain circumstances it may be deemed advisable to employ both the suction box 642 and the blower 6I9. The blower 6I9 may also be directed more nearly tangentially to the sprocket 6|6 as shown in Fig. 3.

The invention is not to be limited to the exact arrangement of parts shown in the drawings or described in this specification as various changes in the details of construction may be resorted to without departing from the spirit of the invention. Various other materials of either an inorganic or an organic nature may also be attenuated by means of the present invention as for example, artificial silk, Nylonf vinyl acetate, cellulose acetate, resins, sugar, etc. Moreover. the illustration of the fibers, especially as they are being crimped is diagrammatic since it is almost impossible to depict these fibers as they move at such great speeds.

Modifications and variations may be resorted to within the spirit and scope of the invention as defined in the appended claims.

I claim:

1. The method of producing crimped fibrous glass which comprises flowing a stream of molten glass into tangential contact with a cage comprising an annular series of parallel bars and revolving at high speed and directing an air jet against said stream and bars to cause tractive engagement therebetween.

2. The method of producing crimped fibrous glass which comprises flowing a stream of molten glass into tangential contact with a cage oomprising an annular series of parallel spaced bars and revolving at high speed while simultaneously directing a blast of agaseous medium against the stream in a direction to forcethe same against said bars and loopwise into the spaces between the bars.

3. The methodof producing crimped fibrous glassvwhich comprises flowing a stream of viscous glass into tangential contact with a cage comprising an annular series of equally spaced crimping bars and revolving at high speed while simultaneously directing against the stream blasts of air in a direction substantially radial to the series with the blasts spaced apart a distance equal to the distance between adjacent bars to force the stream against the bars and between adjacent bars.

4. 'I'he method of producing crimped fibrous glass which comprises flowing a stream of viscous glass into tangential contact with a cage comprising an annular series of spaced parallel crimping bars and revolving at high speed while simultaneously directing blasts of air against said stream in a direction to force the same against said bars and between adjacent bars.

5. The method of producing a crimped glass fiber which comprises projecting a fiber of substantial sinuous conguration while it is still sufliciently hot from its forming operation to permit permanent deformation thereof into a quiescent atmosphere longitudinally at a sumcient rate of speed to cause the undulations thereof to pile up onJeach other and increase their magnitude.

6. The method of producing a crimped glass AfiberV which comprises projecting a fiber of sub- Igreater than the speed of stream now, and establishing a differential air pressure on the inner and outer side of the series of bars to force the stream against said bars and between adjacent bars in the region of contact between the stream and the bars.

8. Apparatus for producing crimped glass fibers comprising a drum having spaced slots in its surface, means for revolving said drum about an axis, means for flowing a continuous stream of Amolten glass against said drum positioned relative to said drum to cause said stream to contact the drum in substantial tangential relationship and means for directing a current of air toward the drum at a stationary localized area and against said stream in the vicinity of the drum.

9. Apparatus for producing glass fibers comprising a foraminous drum, means for revolving said drum about an axis, means for flowing a stream of molten glass against said drum i-n substantial tangential relationship thereto, means for directing a current of air toward the drum and against said stream in the vicinity of the drum, a shield in the vicinity of the drum for restricting the field of air disturbance caused by rotation of the drum, there being a-n opening through the shield through which the stream passes after it has passed the drum.

10. In an apparatus of the character described,

' Y a crimping ldrumagainst which a stream of molten glass is adapted to be pressed to produce a crimped glass fiber, said drum comprising spaced endu plates, and an annular series of` crimping bars extending between the end plates in parallel relationship. means for rotating said drum, and means for creating a differential air pressure between the insideA and outside of said drum at a localized -area stationary relative Vto the drum to force fibers against said drumand thereby be attenuated.

11. The method of producing fibrous glass which comprises flowing streams of molten glass into tangential contact with an annular foraminous surface moving rotatively at high speed, causing tractive engagement between the streams and the surface by simultaneously directing blasts of a. gaseous medium 'against the streams in a direction substantially tangential to the annular surface to force the streams against said surface, thereby attenuating the streams into bers, and causing the fibers after leaving said surface to be carried in the path of air disturbance created by said blast.

12. The method of producing fibrous glass which comprises flowing streams of molten glass into tangential contact with an annular foraminous surface moving rotatively at high speed, causing tractive engagement between the streams and the surface by directing an air jet against said streams and surface in a region stationary relative to the movement of said foraminous surface to hold the streams against the surface and thereby attenuate the streams into fibers, and then causing said fibers to ily freely through the atmosphere and be deposited on an arresting surface.

13. 'I'he method of producing crimped fibrous glass which comprises flowing streams of molten glass into tangential contact with an annular slotted surface moving rotatively at high speed, simultaneously directing a blast of air against said streams in a direction to force the same against said surface and into the slots thereof to attenuate the streams into fibers of substantially wavy configuration, projecting the bers while still hot from their forming operation in the general direction of their length away from said annular surface, and causing a deceleration of the lengthwise moving fibers at a rate sufiicient to cause the undulations thereof to pile up on each other and increase their magnitude.

y 14. The method of producing crimped fibrous glass which comprises flowing streams of molten glass into tangential contact with a cylinder comprising an annular series of spaced bars and moving rotatively at high speed, simultaneously directing blasts of air against said streams in a direction to force the same against said bars and into the spaces between adjacent bars to attenuate the streams into fibers of substantially sinuous configuration, projecting the fibers while still hot from their forming operation into a relatively quiescent atmosphere longitudinally at a sufficient rate of speed to cause the undulations thereof to pile up on each other and increase the magnitude of at least some of the undulations, a-nd then causing said crimped fibers to be deposited on an arresting surface in the form of a felted mass.

15. The method of producing crimped fibrous glass which comprises owing a stream of molten glass into contact with a surface formed of a series of spaced bars, moving the surface in its plane at high speed in the general direction of stream ow, causing tractive engagement between the stream and said surface by directing a gaseous blast against the stream in a direction to force the same against the surface and into the spaces between the bars to attenuate and crimp said stream,

16. The method of producing fibrous glass which comprises applying an attenuating tensive force to a stream of molten glass owing from a source of molten material by causing said stream to contact a foraminous surface, establishing differential gaseous pressure on opposite sides of said surface at the area of contact between said stream and said surface to force the stream against the surface, and moving said surface at high speed relatively to the area of diiferential pressure and in a direction parallel with said surface and generally away from said source of molten material.

17. Apparatus for producing crimped glass fibers comprising a movablemember provided with an endless perforate surface, means for moving said member in a direction to cause a portion of the said surface to move in a plane, means for flowing a stream of molten glass against said portion and in the general direction of movement of the surface in the region of contact between surface and stream, and a blower stationary relative to the movement of the surface of said member for directing a current of gaseous medium toward said portion and against said stream.

18. Apparatus for producing crimped glass bers comprising a drum, the surface of said drum being formed of an annular series of spaced bars, means for revolving said drum about an axis, means for flowing a stream of molten glass against the surface of said drum in substantial tangential relationship thereto, a blower directed toward the axis of the drum for directing a current of air toward the drum and against said stream in the vicinity of the drum.

19. Apparatus for producing glass fibers comprising a foraminous drum, means for revolving said drum about an axis, means for flowing a stream of molten glass against said drum in substantial tangential relationship thereto, a relatively stationary blower directed toward the drum in substantially tangential relaionship with the surface thereof for directing a current of air against said stream in the vicinity of the drum, thereby forcing said stream against said drum to attenuate said stream into a ber and serving to convey the fiber away from the drum.

20. In an apparatus of the character described, a crimping drum against which a stream of molten glass is adapted to be pressed to produce a crimped glass fiber, said drum comprising an annular series of crimping bars extending across the drum in parallel relationship, and means for creati-ng a differential air pressure between the inside and outside of said drum at a localized area to force fibers against said drum and be attenuated thereby, said area of differential air pressure being stationary relative to the drum.

21. Apparatus for producing crimped glass fibers which comprises an attenuating drum having a foraminous annular surface, a blower directed toward said drum to cause a blast of air to pass through said surface, means for rotating said drum relative to said blower whereby the annular surface moves past said blower, and means for flowing a stream of molten glass into tangential contact with said drum in the region of coaction between said blast and said annular surface.

STUART M. DOCKERTY. 

